feat: use Web Worker for OBJ loading to prevent UI blocking (#7846)

## Summary

- Replace OBJLoader with OBJLoader2Parallel from wwobjloader2
- OBJ parsing now runs in a Web Worker, keeping UI responsive
- Add 100MB file size limit with user-friendly error message

reduce loading time for 97M obj from 9s to 3s

fix https://github.com/Comfy-Org/ComfyUI_frontend/issues/7843

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-7846-feat-use-Web-Worker-for-OBJ-loading-to-prevent-UI-blocking-2df6d73d36508140bea3c87e83d11278)
by [Unito](https://www.unito.io)

package.json

@@ -187,6 +187,7 @@
     "vue-i18n": "catalog:",
     "vue-router": "catalog:",
     "vuefire": "catalog:",
+    "wwobjloader2": "catalog:",
     "yjs": "catalog:",
     "zod": "catalog:",
     "zod-validation-error": "catalog:"